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Someone know a bit about Generators? (windmill project)

  1. Feb 6, 2015 #1
    Hi just started working on a hobby project with making a wind mill. I got to the part were i have made the blades and the casing, for the wind mill. I was wondering what type of generator should i use for a 1,5m diameter blade. I really don't have anything special that i want the power to go to. At the moment i just want to see how much power my wind mill is making compared to a real one. That also is a scale of 1,5m diameters on the blade.

    Oh yes and another question was if someone knows if you really need a transmission to get a real effect on the generator. The blades on the wind mill turn realy good now with just 2ms of wind.

    Thanks in advance.
  2. jcsd
  3. Feb 6, 2015 #2


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    If your blade is fixed geometry then it will operate best at a specified angle of attack. If you try to take too much power you will stall the blade airfoil and so greatly reduce the power available. If you take too little power you will not have sufficient angle of attack and will not get all the power available.

    Power is torque * RPM. You need a generator / alternator that will somehow regulate the power extracted from your windmill to optimise the angle of attack of the blades. That will probably need intelligent control of a field winding to optimise RPM at different wind speeds.
  4. Feb 6, 2015 #3

    jim hardy

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    Gold Member

    For experimenting you might do well with bicycle chain & sprockets , and a salvage yard car alternator.
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